Abstract
The knowledge of embryonic and larvae development of fishes is a fundamental key which enables a closer approach to their biology and taxonomy. The present study aims to characterize piracanjuba (Brycon orbignyanus) embryonic and larvae development. During the whole embryogenesis, 15 to 20 embryos were sampled and analyzed. Eggs of B. orbignyanus are semidense, transparent, spherical, and bear a large perivitelline space. Hatching takes place 18 hours and 30 minutes after fertilization at 25 ± 0.8ºC. Total length and weight of just hatched larvae were 4.46 ± 0.39mm and 2.56 ± 0.73mg, respectively. Larvae presented entirely developed and pigmented eyes, as well as a vertical mouth opening of 15.2 ± 1.9% of body length, 36 hours after hatching, period from which intense cannibalism was observed
Highlights
Known as piracanjuba or pracanjuba, (Brycon orbignyanus), (Valenciennes, 1849) is a fish species broadly distributed in South America, which is found in the following rivers: Paraguay, Paraná, lower and medium Uruguay, and Prata (Gery et al, 1987; Cavalcanti, 1998)
The mean value of water temperature during incubation was 25.0 ± 0.8oC, it slightly decreased from the begging of the experiment from 25.9 to 24.0oC in the end
Piracanjuba (Brycon orbignyanus) eggs present similar characteristics to those found in other species (Brycon cephalus, Brycon insignis) belonging to the same genus, such as the total diameter and the large perivitelline space (Bernardino et al, 1993; AndradeTalmelli, 1997; Andrade-Talmelli et al, 2001)
Summary
Known as piracanjuba or pracanjuba, (Brycon orbignyanus), (Valenciennes, 1849) is a fish species broadly distributed in South America, which is found in the following rivers: Paraguay, Paraná, lower and medium Uruguay, and Prata (Gery et al, 1987; Cavalcanti, 1998). Due to its fast growth in captivity, omnivorous food habit, good acceptance of artificial feeds and low food conversion rates, it has been considered a promising species for fish farming (Cavalcanti, 1998). Nowadays, deforesting and presence of a great amount of dams, have diminished piracanjubas landings, reducing and restricting its wild populations to small regions of the Uruguay River basin (Zaniboni-Filho and Schulz, forthcoming) and Paraná River (Gery et al, 1987). There are more than 130 major reservoirs in Paraná river (dam > 10m high); among these, 20% are larger than 10,000 ha (Agostinho et al, in press) reducing with this great part of the lotic area of the river and covering many of the places of growth of the larvae fish
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
